All plants have soil preferences based on the conditions in their native habitats. Matching these as closely as possible will create the ideal conditions for your plants to thrive. You must also account for factors that might slightly change a species’ soil preference, such as your climate or humidity level, whether you’re growing it in a container or in-ground, and so on.
Although soil choice is important for all plants, it is even more vital to consider when growing succulents. Some plants can adapt to different types, but succulents are incredibly picky about their soil due to their sensitive roots and harsh native habitats.
Most succulents come from desert-like environments where there is little rainfall. To manage the lack of moisture, they store additional moisture in their leaves, which gives them a plump appearance. They are accustomed to sitting in dry, sandy, or rocky soil and absorbing what little water they can from quick rains before the excess drains away.
The key to replicating these conditions is drainage. Succulent soil must drain well and quickly to ensure the roots are never sitting in water. Soggy (or consistently damp) soil will cause the roots to rot, ultimately killing the entire plant.
Whether you’re planting in beds or in containers, there are ways to adjust your soil to create the best mix for succulent plants.
Understanding Your Soil Type
For successful succulent planting in beds, amend for optimal drainage.
If you’re planting your succulents in beds and not containers, creating the best soil for succulents should start with understanding your existing soil type. You may not have the perfect soil for succulents in your backyard (most gardeners don’t), but with a few amendments, you can create the ideal environment.
Soil is typically split into four general categories – sand, silt, clay, and loam. Sandy soil drains quickly and retains fewer nutrients, while clay locks in moisture and allows little airflow. Silt retains some moisture and compacts quickly. Loam is a combination of all three of the other types.
The quickest way to test your soil is to squeeze it in your hand:
- If it holds together, it’s closer to clay.
- If it holds shape but crumbles slightly, you have loam.
- If it breaks up immediately and falls through your fingers, it’s sand.
- If it holds shape for a moment but then begins oozing apart, it’s silt.
The latter is the type you’re looking for, taking a clue from the desert environments where most succulents originate. These plants thrive in gritty soil with few nutrients and little moisture. If your garden soil doesn’t quite match up, you can amend it with coarse sand or gravel to boost drainage and create the most suitable texture for succulents.
If your soil is close to sandy but doesn’t drain quite well enough, amendments like sand, gravel vermiculite, or perlite are still important. But if you’re dealing with heavy clay that may turn into a caked mess when amending with sand, you’re better off planting in containers and making your own potting mix instead.
Components Of Succulent Potting Mix
If you’re planting in containers rather than directly in the garden, soil is much easier to manage. You have complete control over what goes into the container, allowing you to combine components to create the perfect soil mix for your plants.
There are a few different components that go into succulent mixes, each with its own uses:
Potting Soil
Use potting soil as a component, but not the sole one, for succulent mix.
Potting soil is the base of your succulent mix. It should not be the only component, as potting soil is usually too dense and retains too much moisture for container succulents. However, it adds the necessary organic matter and nutrients that succulents require to thrive in a pot.
Sand
Add coarse sand to mimic desert conditions, promoting drainage for succulents.
Next on the list is coarse sand, which is used to replicate the sandy conditions these plants are used to. Sand doesn’t hold onto much moisture, allowing any excess to drain away rather than hanging around the roots. Horticultural or building sand is the best source, unlike the finer particulate sizes of beach or playbox sand.
Perlite
Perlite, an expanded volcanic glass product, enhances drainage and root airflow.
Perlite is made from expanded volcanic glass, forming small white balls resembling polystyrene. It is often used in houseplant potting mixes to improve drainage. This material increases the space between particles, improving drainage and airflow around the roots.
Other Options
To enhance moisture retention, consider compost or coconut coir.
While these are the three main components, they are not the only options.
For improved moisture retention to supplement your potting soil, you can use compost or coconut coir, as long as you don’t use too much. Avoid using garden soil in potting mixes, as you may transfer pest and disease issues or weed seeds to your succulent containers. Add materials like perlite, pumice, or fine gravel to boost drainage.
While some people use worm castings to improve moisture retention, it’s best to skip those for succulents. They hold so much extra moisture (up to 10 times their own weight in moisture) that it’s easy to add too much.
You can use whatever you have on hand to create your potting mix. However, each material has slightly different impacts, so adjust your ratios accordingly when mixing.
Making Your Own Succulent Potting Mix
Combine potting soil, sand, and perlite in a 2:2:1 ratio for a basic succulent mix.
Once you’ve gathered your materials, it’s time to put them together to create your own succulent potting mix.
While it’s not an exact science like any baking recipe, your potting mix recipe should follow a general ratio of just over one-third moisture-retaining materials and just under two-thirds drainage materials. You can fill the gaps with whatever you prefer, adjusting slightly until you find the ideal texture.
My basic succulent potting mix recipe starts with these ingredients:
- Two parts potting soil
- Two parts coarse sand
- One part perlite
This mix is suitable for most potted succulents, but there are always some exceptions. For succulents highly sensitive to root rot, I add a few handfuls of gravel into the mixture to increase the spaces between particles. For succulents that prefer a little more moisture – often those kept as houseplants like string of pearls – I bump up the potting soil to three parts to stop it from drying too quickly.
Assess the needs of your succulents and adjust this general ratio as needed. Also, consider the environment and the container you’re planting in. For example, a container in full and harsh direct sun for most of the day will dry out much quicker than one in partial shade, potentially needing a little more potting soil than usual.
Remember, succulent containers should always have drainage holes so water can flow freely through to a catchment tray below!
The Easy Route
Simplify the process by buying a labeled succulent potting mix from a nursery.
If all this talk of amendments and ratios is too much for you, there is a much easier route. Instead of making your mix, purchase one from your local nursery or online.
Just look for high-quality potting mixes labeled suitable for succulents and cacti. These are designed to drain better than regular potting soil, ideal for use on succulents. This takes all the worry out of creating the perfect mix, although it does leave you with less control over soil conditions.
Final Thoughts
Soil choice is important for all plants, particularly for succulents needing well-draining, gritty conditions to thrive. Follow this recipe or simply purchase a specialized mix to limit your risk of rot.
